There is provided a water leakage detection device including a water leakage detection unit which is configured to detect water leakage, a water leakage detection circuit unit which is configured to be driven by a DC voltage from a DC power source and apply an AC voltage for detecting water leakage to the water leakage detection unit, and is configured to determine whether water is leaking based on a detection signal of the water leakage detection unit. The water leakage detection unit includes an insulating transformer having a primary side and a secondary side, the second side being connected to the water leakage detection unit, and a water leakage detection determining unit which is connected to the primary side of the insulating transformer.
